Si 3 N 4 Nanoparticle Addition to Concentrated Magnesium Alloy AZ81: Enhanced Tensile Ductility and Compressive Strength

Abstract

This study is aimed at understanding the tensile ductility and compressive strength-enhancing dual function of nanoparticles in a concentrated magnesium alloy (AZ81) nanocomposite. Si 3 N 4 nanoparticles were selected for reinforcement purposes due to the known affinity between magnesium and nitrogen. AZ81 magnesium alloy was reinforced with Si 3 N 4 nanoparticles using solidification processing followed by hot extrusion. The nanocomposite exhibited similar grain size and hardness to the monolithic alloy, reasonable nanoparticle distribution, and nondominant (0 0 0 2) texture in the longitudinal direction. Compared to the monolithic alloy in tension, the nanocomposite exhibited higher failure strain (+23%) without significant compromise in strength, and higher energy absorbed until fracture (EA) (+27%). Compared to the monolithic alloy in compression, the nanocomposite exhibited similar failure strain (+3%) with significant increase in strength (up to +20%) and higher EA (+24%). The beneficial effects of Si 3 N 4 nanoparticle addition on tensile ductility and compressive strength dual enhancement of AZ81 alloy are discussed in this paper.